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Comment Re:Stupid lack of nonrelativistic propulsion. (Score 1) 102

Rockets being the only solution does not automatically mean rockets are a viable solution. Please quit ignoring the real challenges presented.

Unfortunately, this can't be approached as an engineering problem and get the result you would like. It needs to be approached as a problem in fundamental research of the physics underlying our world.

There were lots of efforts to miniaturize the vacuum tube. They only resulted in smaller tubes. It took new insights in fundamental physics before people could understand how to make a transistor. There were many experiments with germanium (a natural semiconductor) that could have led to the transistor before 1947 if anyone had understood what was happening.

Comment Re:Puh-lease (Score 1) 102

Look at the amount of money made on oscillococcinum, and you might agree it's a successful hack to make money from the stupidity of others.

This would be cool if it was more than a stage trick. The superconductor needed to do this used to be mail-ordered from Edmund Scientific. So lots of hackers were doing levitation demonstrations in the 90's. People think it's cool because they've not lived through that, or have forgotten it.

Comment Puh-lease (Score 1) 102

Before someone makes a working hoverboard, we will first hear about the principle that makes it possible. Because one that's practical is almost guaranteed to get someone a Nobel Prize. And certainly Lexus would go for that if they could.

No new principles lately. There is an existing principle of magnetic repulsion that would work only in an extreme condition. One requiring really special stuff buried in the street, and probably including liquid nitrogen to keep it working for even a short time and a few feet.

So, it's a gimmick.

Comment Re:Wealth inequality (Score 1) 940

For renters it is pushing out people with lower incomes. Not everyone (due to rent control in areas), but still quite a lot of people are getting pushed out I think.

For existing lower-income homeowners it creates an opportunity to get a really good price for their home and then move to cheaper environs. (aka Gentrification).

The remaining pre-existing homeowners are not necessarily going anywhere. Prop 13 means that their property taxes are not changing radically and living costs are otherwise on a less steep ramp.

Gentrification is a two-edged sword, for sure, but I'm not sure that anything can really be done about it. The people protesting the changing nature of their neighborhoods are in the same economic class as many of the people selling and moving away. A person from group A can't really force a person from group B to not sell their home.

-Matt

Comment Re:Who buys them? (Score 1) 668

So... An Osteoptath takes a "holistic" approach, and yet the treatment is only being used for certain musculosceletal conditions? How does only being useful only for that specific thing make an Osteopath more "holistic" exactly?

Of course, we haven't even gotten into the fact that osteopathy hasn't even been demonstrated to have an actual effect on musculoskeletal conditions...

Comment Blame posix (Score 1) 233

Blame posix for making all the goddamn pthread *_timedlock() calls take an absolute real time instead of a monotonic clock.

In anycase, I'm not even going to bother doing anything fancy. I'll let the system suddenly be one second off and then correct itself over the next hour. I'm certainly not going to do something stupid like letting the seconds field increment to 60. Having the ntp base time even go through these corrections is already dumb enough. Base time should be some absolute measure and leap seconds should just be adjusted after the fact in a manner similar to timezones.

-Matt

Comment TRIM -- command of mass destruction (Score 5, Interesting) 182

The only TRIM use I recommend is running on it on an entire partition, e.g. like the swap partition, at boot, or before initializing a new filesystem. And that's it. It's an EXTREMELY dangerous command which results in non-deterministic operation. Not only do SSDs have bugs in handling TRIM, but filesystem implementations almost certainly also have ordering and concurrency bugs in handling TRIM. It's the least well-tested part of the firmware and the least well-tested part of the filesystem implementation. And due to cache effects, it's almost impossible to test it in a deterministic manner.

You can get close to the same performance and life out of your SSD without using TRIM by doing two simple things. First, use a filesystem with at least a 4KB block size so the SSD doesn't have to write-combine stuff on 512-byte boundaries. Second, simply leave a part of the SSD unused. 5% is plenty. In fact, if you have swap space configured on your SSD, that's usually enough on its own (since swap is not usually filled up during normal operation), as long as you TRIM it on boot.

-Matt

Comment Re:Let's be honest about the purpose of the hyperl (Score 1) 124

Hey, I hang out with a lot of creative people. Not Elon Musk, but Steve Jobs for more than a decade, and lots of people at least as smart that you don't know. They can be really brilliant, and successful, and they can still make really stupid mistakes and sell them to the rest of us pretty well because they believe in themselves completely and they have a track record. I've done that too.

That's the hyperloop. Something Elon never meant to stand behind (and still really isn't), just put out there to torpedo a worthy project that he didn't believe in.

Anyone who looks at the hyperloop design can see it's not a no-brainer. It has safety issues up the wazoo :-) It's going to take a long time to get right.

Meanwhile, little Switzerland can have incredible trains everywhere and the United States can't get it together, and unlike with rockets and cars Elon's not helping this time. And I am not sure that the "lease" part of his solar business is a great thing for the world either.

Comment Let's be honest about the purpose of the hyperloop (Score 3, Interesting) 124

Although the hyperloop is possible and might even be practical someday, let's please be honest about the reason it was created. Elon Musk just wanted to kill the California high-speed rail.

That might have been OK if there was a hope that we could actually replace it practically with a hyperloop. But given the history of bleeding-edge rail - ride any maglevs lately? We haven't even had much success with monorails outside of theme parks and Las Vegas - we don't really have any working system to replace high-speed rail. Hyperloop should really be called "Pipes that carry People" and we need decades of work on it before considering intercity lines.

Comment Sheesh, 4K isn't obsolete yet! (Score 1) 181

I mean, come on... just when the graphics performance starts to get good, people all want bigger displays which halves the performance and then want to go even BIGGER and halve it again.

My perfectly good Sandybridge i7 can't drive this shit. Time to rotate in another workstation. Again.

Grumble.

-Matt

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